$ { \left[\begin{array}{rr}{2} & {0} \\ {1} & {-2} \\ {0} & {4}\end{array}\right]-\left[\begin{array}{rr}{0} & {2} \\ {4} & {2} \\ {0} & {3}\end{array}\right] = {?} } $
Solution: To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rr}{2}-{0} & {0}-{2} \\ {1}-{4} & {-2}-{2} \\ {0}-{0} & {4}-{3}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{2} & {-2} \\ {-3} & {-4} \\ {0} & {1}\end{array}\right]}$